The statements in this section merely provide background information related to the present disclosure and may not constitute prior art.
In a typical shaft seal, a flexible lip protrudes outwardly from an elastomeric body to form a lip seal for sealing about a rotating shaft. A lip seal retains lubricant on an oil side of the seal and prevents the entry of contaminants from an air side of the seal.
A lip of such a shaft seal is subjected to bending loads and stresses, which reduce the life of the lip. Oftentimes, the lip is integrally molded with the body from an elastomeric material such as rubber.
The present disclosure includes a shaft seal having a lip. A plurality of supports are provided to support the lip and increase its effective life. An outer case, an insert, a backup insert and an inner case are provided to provide lip supports.
In a preferred embodiment, a shaft seal includes an annular inner case having an axially extending leg and a radially extending leg extending radially inwardly from an end of said axially extending leg; an inner annular insert positioned radially inside of said axially extending leg of said inner case; an elastomeric annular body overmolded to said inner case and including a radially inwardly protruding annular lip, an axially extending annular bead and at least one radially outwardly extending annular bead; a backup annular insert received in an annular pocket in a radially outer surface of said elastomeric annular body; and an annular outer case having an axially extending leg disposed against said at least one radially outwardly extending annular bead of said elastomeric annular body and a radially inwardly extending leg disposed against said axially extending annular bead of said elastomeric annular body.
Further areas of applicability will become apparent from the description provided herein. It should be understood that the description and specific examples are intended for purposes of illustration only and are not intended to limit the scope of the present disclosure.